Combustion chamber for direct injection of fuel into exhaust recirculation rich mixture

Abstract

An internal combustion engine defining a combustion chamber for the direct injection of fuel through a centrally located fuel injector and having a first inlet passage and port for directing hot exhaust gases of a recirculation medium to a central region of the combustion chamber and a second inlet passage and port for directing air tangentially into the combustion chamber to cause a circular flow about the chamber's periphery and about the exhaust rich central region. The injector sprays fuel through the hot exhaust gas medium in the central region which results in a pre-heating of the fuel which has been found to reduce hydrocarbon emissions prior to ignition by a spark plug located adjacent the periphery of the combustion chamber.

What is claimed is: 
     
       1. An induction system and combustion chamber for a spark ignited internal combustion engine with direct fuel injector to introduce fuel directly into the combustion chamber, comprising: the engine combustion chamber having two inlets thereto, a first inlet oriented tending to introduce air tangentially into the combustion chamber to produce a generally circular motion in a peripheral region of the combustion chamber and about a vertical axis, a second inlet oriented to introduce air generally toward the center of the combustion chamber tending to produce a rolling air movement about a horizontal axis;   a source of exhaust gases from the combustion chamber being fluidly connected to said second inlet so that an exhaust gas rich region is produced at the central portion of said combustion chamber;   a fuel injector located centrally of said combustion chamber with fluid outlets to spray fuel generally in a radially outward direction through the exhaust gas rich central region and into the peripheral region of the combustion chamber, whereby fuel is heated by the exhaust gases;   at least one spark igniter located in the peripheral region of the combustion chamber for selectively igniting a mixture of fuel and air in the peripheral region.   
     
     
       2. In a spark ignited type internal combustion engine of the type having a combustion chamber with fuel injector for passing fuel directly into the combustion chamber, a fluid distribution system for passing air and exhaust recirculation gases into the combustion chamber, comprising: the combustion chamber having two inlets thereto, a first inlet oriented to direct a flow of air in a generally tangential direction into the chamber to produce a circular motion about a generally vertical axis, and a second inlet oriented to direct a flow of air toward a central region of the combustion chamber to produce circular motion about a generally horizontal axis,   a source of exhaust gases;   an exhaust gas inlet fluidly connected to said second combustion chamber inlet;   selectively positioned valve means for controlling the quantity of exhaust gases passed into said second inlet to produce an exhaust gas rich central region in said combustion chamber under certain operating conditions;   a fuel injector located centrally of said combustion chamber, said fuel injector having outlets to cause fuel to spray in a substantially radially outward direction toward the periphery of the combustion chamber and through the exhaust gas rich central portion, wherein the fuel is heated by the exhaust gases;   at least one spark igniter located adjacent the periphery of the combustion chamber for selectively igniting the mixture of fuel and air in the outer region of the combustion chamber surrounding the exhaust gas rich central region.   
     
     
       3. The combustion chamber and fluid distribution system for passing air and exhaust recirculation gases into the combustion chamber as set forth in claim 2 in which the valve means controls the ratio of air and exhaust gases passing through said second inlet. 
     
     
       4. The combustion chamber and fluid distribution system for passing air and exhaust recirculation gases into the combustion chamber as set forth in claim 2 in which two spark plugs are positioned adjacent the peripheral edge of the combustion chamber and located generally opposite to one another to either side of the centrally located fuel injector. 
     
     
       5. The combustion chamber and fluid distribution system for passing air and exhaust recirculation gases into the combustion chamber as set forth in claim 2 in which said fuel injector is positioned centrally and in series flow relation to said second inlet. 
     
     
       6. The combustion chamber and fluid distribution system for passing air and exhaust recirculation gases into the combustion chamber as set forth in claim 5 in which said fuel injector has an obliquely inclined annular surface within said combustion chamber through which a plurality of fuel outlet orifices are extended so that fuel is mainly directed radially outward in the combustion chamber through the exhaust gas rich central region.